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Habitability Of Surrounding Planets Affected By Super Flares Of Red Dwarfs: NASA

Red dwarfs -- especially young red dwarfs -- are active stars, producing flares blast out energy

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US shutdown delays space missions but NASA not grounded: Report,

Using NASA’s Hubble Space Telescope, astronomers have found that violent outbursts, or superflares, from red dwarf stars could affect the habitability of any planets orbiting it.

Young low-mass stars flare much more frequently and more energetically than old stars and middle-age stars like our Sun, the findings of the study published in the Astrophysical Journal showed.

The findings are based on observations of the flare frequency of 12 red dwarfs.

Hubble is observing such stars through a large programme called HAZMAT — Habitable Zones and M dwarf Activity across Time.

“M dwarf” is the astronomical term for a red dwarf star — the smallest, most abundant and longest-living type of star in our galaxy.

Hubble Telescope. red dwarf
Hubble Telescope. Flickr

The HAZMAT programme is an ultraviolet survey of red dwarfs at three different ages — young, intermediate, and old.

“The goal of the HAZMAT programme is to help understand the habitability of planets around low-mass stars,” explained the programme’s principal investigator, Evgenya Shkolnik from Arizona State University.

“These low-mass stars are critically important in understanding planetary atmospheres,” Shkolnik added.

Stellar flares from red dwarfs are particularly bright in ultraviolet wavelengths, compared with Sun-like stars.

Red dwarf  planet
Artist’s view of planets transiting red dwarf star in TRAPPIST-1 system. Flickr

Hubble’s ultraviolet sensitivity makes the telescope very valuable for observing these flares.

The flares are believed to be powered by intense magnetic fields that get tangled by the roiling motions of the stellar atmosphere.

When the tangling gets too intense, the fields break and reconnect, unleashing tremendous amounts of energy.

The team found that the flares from the youngest red dwarfs they surveyed — just about 40 million years old — are 100 to 1,000 times more energetic than when the stars are older.

This younger age is when terrestrial planets are forming around their stars.

Red dwarf
This illustration shows a red dwarf star orbited by a hypothetical exoplanet. NASA

About three-quarters of the stars in our Milky Way galaxy are red dwarfs. Most of the galaxy’s “habitable-zone” planets — planets orbiting their stars at a distance where temperatures are moderate enough for liquid water to exist on their surface — orbit red dwarfs.

In fact, the nearest star to our Sun, a red dwarf named Proxima Centauri, has an Earth-size planet in its habitable zone.

Also Read: NASA Plans For Science Payloads For Delivery To Moon

However, red dwarfs — especially young red dwarfs — are active stars, producing flares that could blast out so much energy that it disrupts and possibly strips off the atmospheres of these fledgling planets. (IANS)

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Human Sperm Retains Viability in Outer Space Conditions: Researchers

The study was presented at an annual meeting of European Society of Human Reproduction and Embryology in Vienna, Austria

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Each sperm has 37.5MB of DNA information in it.
Each sperm has 37.5MB of DNA information in it.

Researchers have found that human sperm retains its complete viability within the different gravitational conditions found in outer space.

The results could be a huge boost to zillionaires like Amazon founder Jeff Bezos who see the “colonisation” of space as an answer to the Earth’s ever threatened resources.

“If the number of space missions increases in the coming years, and are of longer duration, it is important to study the effects of long-term human exposure to space in order to face them,” said Montserrat Boada from Dexeus Women’s Health in Barcelona, whose group worked with microgravity engineers from the Polytechnic University of Barcelona.

“It’s not unreasonable to start thinking about the possibility of reproduction beyond the Earth,” Boada said.

The study was performed using a small aerobatic training aircraft (CAP10), which can provide short-duration hypogravity exposure.

The plane executed a series of 20 parabolic manoeuvres, providing eight seconds of microgravity for each parabola.

Overall, 10 sperm samples obtained from 10 healthy donors were analysed after exposure to the different microgravities found in space and ground gravity.

To overcome regulatory constraints and increase donor numbers, sperm banks in the UK and Australia began to market the act of donating sperm as a confirmation of masculinity. Pixabay

The sperm analysis comprised a full range of measurements currently performed for fertility testing — concentration, motility, vitality, morphology and DNA fragmentation — and results found no difference whatsoever in any of the parameters between the microgravity space samples and the control group samples from Earth.

Indeed, there was 100 per cent concordance in DNA fragmentation rate and vitality, and 90 per cent concordance in sperm concentration and motility, said Boada.

These minor differences, she added, “were more probably related to heterogeneity of the sperm sample than to the effect of exposure to different gravity conditions”.

Boada described this as a preliminary study and her group will now move on to validate the results and then to larger sperm samples, longer periods of microgravity and even fresh sperm.

Also Read: Xiaomi Confirms First Smartphones Under its New CC Series

One reason for using frozen sperm in this study was the known effect of radiation on fresh sperm, Boada noted.

“Radiation impairs the quality and viability of human sperm, and these effects are expected to be greater on fresh sperm than on frozen samples,” she said.

The study was presented at an annual meeting of European Society of Human Reproduction and Embryology in Vienna, Austria. (IANS)